STV0974 datasheet(12/69 Pages) STMICROELECTRONICS

12 / 69 page

12/61

STV0974

Functional description

Byte ordering assumes a little endian memory system, i.e. in 16-bit formats, the least significant

byte is sent first. For example, the UYVY format produces the sequence U Y0 V Y1... as per [1].

Note:

Nevertheless various options are available to suit memory system requirements:

● Byte ordering can be changed to big endian

● In YUV formats, the U and V components can be swapped

● In RGB formats, the R and B components can be swapped

YUV format processing The RGB pixel is converted to YUV coordinates according to ITU-R

BT601 specification. The YUV coordinates are then rounded and clipped for an 8-bit

representation. To produce a 4:2:2 digital component video, U and V components are filtered and

down sampled by a factor of 2, coincident with Y sampling time.

RGB format processing Dithering: In order to avoid contouring effects on low color depth

displays, the RGB components are dithered prior to truncation to the required number of bits.

Framing: The output frame is produced by performing the following steps:

1 Blanking code insertion: During video blanking intervals, blanking codes are inserted in the

output stream. The default blanking code is the 16-bit pattern 0x1080, corresponding to Y =

0x10 and U/V = 0x80 as per

[1].

2 Synchronization pattern detection and correction: The coder performs detection of various

synchronization patterns and applies a correction according to the current output format.

3 Video Timing Reference Code Insertion: A 4-byte sequence is inserted at the beginning and

the end of each digital video line to delineate lines and frames in the video stream. The

sequence is defined in

[1] as FF 00 00 XY, where the XY byte is defined by:

SAV (Start of Active Video) is defined as the 4-byte sequence where H = 0.

EAV (End of Active Video) is defined as the 4-byte sequence where H = 1.

Table 4: Output video formats

Name

Format

Description

UYVY

Y7Y6Y5Y4Y3Y2Y1Y0 U7U6U5U4U3U2U1U0

Y7Y6Y5Y4Y3Y2Y1Y0 V7V6V5V4V3V2V1V0

YUV (or YCBCR) 4:2:2 format as per [1]

RGB565

R4R3R2R1R0G5G4G3 G2G1G0B4B3B2B1B0

16-bit RGB format for direct viewfinder on 64 K color

LCDs.

RGB444

03020100R3R2R1R0 G3G2G1G0B3B2B1B0

16-bit RGB format for direct viewfinder on 4096 color

LCDs. Uses 4 bit per RGB component, the four MSB’s are

zero padded.

RGB332

R2R1R0G2G1G0B1B0

8-bit RGB format for low bit rate viewfinder usage.

Table 5: XY bits definition

Bit

Symbol

Definition

7 (msb)

Always 1.

Even / Odd Field. To maintain compatibility with

[1], F is alternatively 0 or 1.

V = 1 during field blanking, 0 otherwise.

H = 1 during line blanking, 0 otherwise.

Protection bit: P3 = V xor H

Protection bit: P2 = F xor H

Protection bit: P1 = V xor V

0 (lsb)

Protection bit: P0 = F xor V xor H

STV0974 数据表(PDF) 12 Page - STMicroelectronics

STV0974 数据表(HTML) 12 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69

数据表下载